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By AIME AIME

A STUDY of subsidence and ground movement in the copper and iron mines of the upper peninsula of Michigan has been made by W. R. Crane of the United States Bureau of Mines and published as Bulletin 295 of 66 pages and 49 illustrations. As a result of subsidence, the country adjacent to the mines and over- lying the mine workings in this district is often broken to such an extent as to affect its value; mine shafts and development openings are occasionally so damaged as to be rendered useless, and water can enter the workings through fractures and cave-ins. The problem is more serious in the iron-mining districts, where villages and towns not owned by the operating companies have grown up around mining operations.

Jan 1, 1929

By Robert M. Doerr

The research objective was to determine the effect of aluminum alloy additions on the oxidation behavior of cobalt-nickel alloys. Thirty high-purity alloys were reacted with 02 at 0.5 atm at 1,351°, 1,389°, and 1,429° K in a volumetric apparatus for about 300 min. The alloy compositions consisted of Co-Ni master alloys (0, 22, 50, 70, 91, and 100 wt pct Ni) with aluminum additions of about 0, 1, 2, 4, and 8 wt pet. Large early deviations from, or changes in, the parabolic rate constant were encountered, but in most cases, the reaction rate declined approximately in accordance with the parabolic rate law. A sharp peak in the parabolic oxidation rate constant was observed for specimens containing a to 22 percent nickel and 1 to 2 percent aluminum at 1,351° K, and the rate constants for these compositions were lower at the higher temperatures. Specimens containing 8 percent aluminum reacted far more slowly than did any of the others.

Jan 1, 1971

By J. B. Dilworth

The purpose of this paper is, first, to give a general account of a little-known coal-district of SE. Kentucky, its topography, drainage, and mineral resourcee, for those who may be interested in its economic development; and secondly, so to describe the geologic features of the field as to furnish available data to those engaged on the broader problems of Appalachian coal-geology. The data from which the major portion of the paper has been prepared were obtained, in professional investigations for private individuals and corporations, within the last decade. The area under review, defined by a heavy line on the map, Fig. 1, lies between Little Black and Pine mountains, and extends from Harlan on the west to a N-S. line crossing Looney creek 3 miles from its mouth on the east. This area can be divided for description into a Western and an Eastern Division. The character of investigatioil pursued in the Western Division, below Fugitt creek, was very different from that employed in the Eastern. In the former, only a rapid reconnois-sance was attempted: such coal-openings as had been made by prospectors or by citizens in obtaining fuel were visited, their

Jan 1, 1913

By Marco Olper

The CX-EW technology, developed by B.U.S Engitec, is improved introducing besides the battery paste electrowinning, the direct electrorefining of metallic lead (grids and poles) obtained from CX breakers. This new concept of electrorefming the antimonial lead scrap is aimed to the production of 99.99 lead and of slimes with high antimony content, avoiding gaseous emissions in melting lead scrap, and expensive and pollutant thermic refining operations. In this way, practically all lead content in the battery is available as 99.99 lead, hence with a wider market for the lead recyclers. This paper will describe the tests performed on a pilot plant scale with special reference to the relatively low energy consumption of the process.

Jan 1, 1993

By H. Shafick Hanna

The beneficiation characteristics of low grade Birmingham red iron ores of the Big Seam and Ferruginous Sandstone seams were investigated using flotation and magnetic separation after reduction roasting. Samples of Bib Seam Ore responded more readily to concentration than the Ferruginous Sandstone ores. The impurities inherent with the iron oxide minerals limit the grade of concentrates recoverable from these ores to a maximum of about 61% Fe if reasonable iron recoveries are sought. Flotation concentrates assaying 60-61% Fe and about 0.1% P with attendant iron recoveries of about 63% were achieved from Big Seam ore charges while those obtained from the low phosphorus Ferruginous Sandstone samples analyzed 54-56% Fe. Reductive roasting and magnetic separation of ground charges of the two ore samples yielded concentrates assaying 60-61% Fe. Iron recoveries were better than those achieved by flotation, but the magnetic products of Big Seam ore were high in phosphorus (0.2-0.3% P).

Jan 1, 1983

By Chester O. Ensign

Many publications to date have advocated under- seas mining operations, optimistically overlooking the paucity of information on mineral distribution and the ocean environments in which minerals occur. Such articles (smattered with opinion, as is this article) are herein tempered by my more conservative views on the economics of mining under the seas. For purposes of this paper, underseas mining refers only to the deeper surficial deposits of the continental shelf and the deep sea floor, i.e., the deposits of phosphorite and manganese nodules.

Jan 9, 1966

By A. L. Engel

IN the treatment of complex ores by flotation, one of the most important steps is conditioning the feed. Conditioning primarily consists of the addition, in the grinding circuit, of an alkaline reagent, for example sodium carbonate, which neutralizes any acidity of ore and mill water, counteracts the effect of 'harmful soluble salts, disperses colloids, and provides the necessary alkalinity for the best metallurgical results. The several minerals of the ore should be put in such condition that they may be floated or rejected as desired, through the action of further reagents thereafter used.

Jan 1, 1932

By D Craw

Bulk ore tailings from the Macraes gold mine gold extraction process are stored in a large (ca 0.6 km2, 80 m deep) mixed tailings impoundment whose pH is maintained near 8 by natural rock neutralizing capacity. The mixed tailings will be stored in this impoundment in perpetuity after mining ceases. Confidence in the long term environmental stability of these tailings can be gained from examination of mineralogically and chemically similar geological situations in the immediate vicinity. A sequence, typically about 5 m thick, of sands and gravels derived from the Macraes mineralized zone 12 000 to 28 000 years ago contains rounded detrital sulphide mineral grains which are unoxidized despite close proximity to the surface and occasional incursion of oxygenated waters. Saturating water pH is currently 7-8. Sands with 0.2 to 0.8 wt % organic carbon host sulphate-reducing bacteria (SRB), and localized cementation by authigenic framboidal pyrite has occurred. Comparison of the 28 000 year-old sediments with the modem tailings suggests that similar chemistry will prevail, possibly with deposition of authigenic pyrite in the tailings, in the long term. As long as the present slightly anoxic and circumneutral pH environmental conditions are maintained in the mixed tailings dam, sulphide decomposition and acidification are unlikely. These sediments provide a plausible geological analogue for long-term benign storage of the mixed tailings impoundment.

Jan 1, 2000

By I. Lackey

In 2004, Zinifex Budel Zink commenced testing with the objective to increase the precipitation of aluminium in the iron purification stage of its hydrometallurgical zinc circuit, without the use of expensive reagents. Findings from the literature applied to the leach circuit at Zinifex Budel Zink demonstrated that aluminium removal from the leach circuit could be increased by lowering the ferric concentration and acidity in the vessels where jarosite precipitation occurs. An associated increase in copper precipitation was mitigated by limiting the extent to which the ferric concentration was lowered in the vessels where jarosite forms and lowering the ratio of copper to aluminium in the solutions entering these vessels.

Jan 1, 2006

The following is am incomplete list of members and guests who called at Institute headquarters during the period May 10, 1918 to June 10, 1918. Arthur K. Adams, Potrerillos, Chile. J. M. Mahoney, Wilkinsburg, Pa. John Carter Anderson, Tucson, Ariz. Benjamin L. Miller, South Bethlehem, Pa. George S. Blair, Camp Cordon, Ga. Wilbur A. Nelson, Nashville, Tenn. W. A. Deane, Summitville, N. Y. Miles G. Nixon, Chicago, Ill. Charles H. Fulton, Cleveland, Ohio. Walter G. Perkins, San Francisco, Cal. Rudolf Gahl, Inspiration, Ariz. G. M. Ponton, Ottawa, Canada. C. C. Griggs, Eureka, Utah. D. A. Powell, Columbus, Ohio. J. F. Hanst, Potrerillos, Chile. H. W. Reed, Salt Lake City, Utah. Stanley C. Herold, Pittsburgh, Pa. J. C. L. J. Seelig, Padong, East. Indies. Floyd D. James, Boston, Mass. Oberlin Smith, Bridgeton, N. J. Charles Janin, San Francisco, Cal. Harrison Souder, Cornwall, Pa. E. Horton Jones, Copper Cliff, Ont. Stanley A. Spellmeyer, Camp Meade, Md. William Kelly, Vulcan, Mich. Roger S. Sperry, Waterbury, Conn. Ichiro Kitsunezaki, Tokyo, Japan. D. R. Thomas, Toronto, Canada. P. K. Lucke, San Antonio, Tex. Thor Warner, Phoenix, Ariz. E. Francis McCrossin, Birmingham, Ala. L. Douglass Anderson, formerly superintendent of the United States Smelting Co., Midvale, Utah, is now manager of smelters, Intermountain District, United States Smelting, Refining & Mining Co., Salt Lake City, Utah.

Jan 7, 1918

By Watsford RMS, Schache IS, Slaughter PJ

As part of the overall Copper Smelter expansion activities at Mount Isa Mines from 1970 - 1975, a decision was made to open circuit the converter slag from the Smelter and treat this product by flotation. This paper describes the technical aspects of plant operating and reagent practices employed, with particular emphasis on the large scale milling of this product and the effect through the use of reagent hydroxy ethyl cellulose on chalcocite grade and recovery.

Jan 1, 1978

By Lawrence Devon Smith

"This paper examines the impact of the various assumptions that go into an economic evaluation, and shows how these can be combined to show an exciting result that may not really exist. An example of an embellished case (the kind that one frequently sees when projects are being promoted) is developed and the cumulative impact is analysed to show the actual project underneath. The paper also points out some areas to watch for overly optimistic assumptions such as prices, inflation, and debt. The concept of a ""bare bones"" base case is proposed (constant metal prices, constant dollars, no inflation, no debt, no interest, on a project basis, after tax) as a common reference point.As well, the discount rate is examined as a fundamental means of reflecting risk in discounted cash flow evaluations. Current industry practice is discussed, and a methodology for the analysis of risk levels is proposed that assesses the constituent components of the discount rate: real interest, mineral project risks, and country risk.INTRODUCTIONOften, the first time that all of the technical and economic data for a mineral project comes together in one place is when the economic evaluation is developed. This typically happens when work on the project has progressed to a sufficient level of detail that the effort to produce a year-by-year cash flow is justified, usually at the pre-feasibility or feasibility study stage. The data involved will include:• production; tonnes waste and ore mined, ore grade, mining recovery, metallurgical recovery, metal sold• revenue; metal price, smelting & refining charges, marketing costs• operating Costs; mining, milling, administration, fees, royalties• capital Costs; exploration, development, construction, indirect costs (engineering, management), contingencies, start-up, inventories, working capital, replacement and sustaining capital, closure costs• taxes and royalties• exclusions; depreciation (this is not a cash item), sunk costs (only costs going forward)."

Jan 1, 2003

By W. M. Tuddenham

It would be most difficult to place a date on the beginning of the revolution in analytical techniques that we have witnessed in recent years; but there is no question that the period since the end of World War II has seen a major change in thinking with respect to control and accounting analyses. For reasons relating to competition, much of this change was brought about in the chemical industries and only more recently has begun to affect directly the mineral industries. In considering the subject outlined in the title of this paper, one might well be tempted to discuss solely the more exotic methods of control and automation which have come into being in the past short while. In this paper, however, an attempt will be made to take a broader view and consider not only the application of newer purely physical methods of control but also those phases of chemical plus physical analyses that have bearing on our industry.

Jan 1, 1962

By C. W. P. Finn

INFACON is of special significance to people in South Africa who are interested in ferro-alloys, because it was in South Africa that the idea of regular international congresses on ferro-alloys was conceived and developed. INFACON 74, the first-ever such congress, was held in Johannesburg from 22nd to 26th April, 1974, being organized by the South African Institute of Mining and Metallurgy, the National Institute for Metallurgy, and the Ferro Alloy Producers' Association of South Africa. Design Awards The Design Institute is inviting entries for the 1981 Shell Design Awards. Any product that falls into the three categories shown below, and that was designed in South Africa and is in production, is eligible for an award. Since their inception in 1970, the Shell Design Awards

Jan 1, 1981

GENTLEMEN, lt is with much pleasure I meet you tonight at this the second meeting of the Australasian Institute of Mining Engineers, held in Western Australia, and I sincerely thank you for the honour you have conferred upon me in electing me as your President. I greatly appreciate the distinction, and will endeavour to fulfil the duties of the office to the best of my ability, and hope to prove a worthy successor to those gentlemen who have held the position before me. On behalf of the local members of the Institute, I extend a hearty welcome to the members from the other States of the Commonwealth, who have come so far to attend this meeting, and also to the non-members whom we have invited this evening. We are especially pleased to have Mr. Gregory, our Minister of Mines and Railways, and the Government and School of Mines officials with us; and I take this opportunity to thank the Premier, Mr. Gregory, and the Government officials for the assistance given us, and for doing so much to make the visit of our members from the other States so pleasant and instructive. I have also to thank the Mayor and Councillors of Kalgoorlie for the courtesy and hospitality given to our members, which is much appreciated.I assume you want me to follow the time-honoured custom of giving a Presidential address...

Jan 1, 1909

By Mehdi Asadi, Heinz Palkowski

"In recent years, the increased demand for advanced high-strength steels (AHSS) mainly had been driven by the need of the automotive industry to reduce weight and to improve safety. Beside good ductility and high strength, those steels have a high bake hardening (BH) effect, giving additional contribution to the strength of structural parts, subjected to the paint baking process. In this paper we concentrate results gained for hot rolled dual phase (DP) steels.For the simulation of changing process conditions within the final hot rolling the specimens were hot deformed using different schedules of temperatures and reductions, selected according to the non-recrystallization temperature (TnRX). It was possible to refine the DP steel structure by control-ling the deformation temperature and the amount of strain below TnRX during the thermo-mechanical controlled processing (TMCP). This structure refinement resulted in an improvement of the strength and BH behaviour. A wide spectrum of mechanical properties could be obtained depending on the different hot deformation schedules. The best strength and BH levels were recorded for the deformation below TnRX at the highest amount of strain.IntroductionDP steels are characterized by a good formability, high strength and a good compromise between strength and ductility [1]. Moreover, the DP steels exhibit a continuous yielding behaviour, low yield point and a high strain-hardening coefficient [2]. Furthermore, the DP steels often show a large potential for bake hardening (BH). BH refers to the increase in yield strength as a result of the paint baking treatment of the shaped auto-body parts. The primary mechanism that causes the additional strengthening is the immobilization of dislocations by the segregation of interstitial atoms, known as classical static strain aging [3]. The increase of strength thus achieved allows a further reduction of sheet thickness and improves the crash safety and the dent resistance. The BH of special steel qualities is technically used in DP, where e.g. the increase in strength is realized in the final heat treatment [4]. Previous own investigations [5-6] stated that the BH effect of DP is much stronger than that one for conventional BH steels."

Jan 1, 2012

Provide reasonably priced, reliable fire protection for blasthole drills. Approach An automatic fire sensing and suppression system using both dry and gaseous chemicals was developed, and is more shock and vibration resistant than similar industrial fire protection systems. How It Works Temperature sensors mounted in the drill's machinery house, hydraulic room, operator cab, and transformer area detect the heat from a fire, and trigger a sequence of actions. The same fire fighting sequence can be initiated from manual alarm boxes in the cab, hydraulic room, or machinery house. Electrical power to the drill Is immediately cut off, and a horn sounds to warn the drilling crew. After a 40-second, built-in, delay to allow time for drill's ventilating fan to stop, gaseous and dry chemical fire extinguishing agents are piped to and released in various rooms of the drill. The gaseous extinguishing agent (Halon 1301) is released in the machinery house, hydraulic room, and operator cab where dry chemical clean-up from electrical panels and machinery would be difficult and costly. Dry chemical is piped to the transformer room at the rear of the machine. Location of the principal components of the system are shown in the drawing.

Jan 1, 1979

By Bronwynne K. Williams

"In deriving flotation kinetic models, the froth phase was, until recently, either ignored or treated entirely empirically. The behaviour of the froth is now known to be usually important and sometimes dominant in determining flotation performance. Hence numerous methods have been developed for sampling the flotation froths and models incorporating the effects of the froth behaviour have been derived.Such models will assist in determining more accurate estimations of the kinetic parameters utilised in the designing of industrial scale plants thus reducing the incurred costs of over designing. In particular, improved models for batch tests may lead to more effective use of batch testwork for prediction of continuous plant behaviour. A more detailed model is thus proposed which allows for a more realistic approach to the flow distribution in the froth phase.PROPOSED MODELThe batch flotation process is split into two stages in time, namely before the froth begins to overflow and after. The assumptions made, and hence the calculations, are different for each stage.The air enters the slurry at t=0 and generates froth. The superficial velocity of the air through the cell is given by go. It is assumed that the rate of froth breakage (gb) is constant during the first stage. The froth rises with a uniform net velocity throughout the cell and no mixing is assumed to occur.After the froth begins to overflow, the velocity distribution of the gas is modeled by segmenting the froth phase as shown in Figure 1. A model for bubble breakage rate or measurements of froth velocity allows one to obtain the volumetric rate of concentrate froth production. The entrained water and associated particles and a drop-back mechanism are also allowed for in the model."

Jan 1, 2003

By D. O. Wyble

Five water-driver fields, for which pressure predictions had been made within a few years after discovery, were re-studied when four to five years of additional pressure and production data became available. It was fortnd that forecasts of the pressure in water-dri~fe reservoirs may be subject to considerable unccrtainty. Predictions car be erroneous when there is insufficient presswe history to define the cllaracteristics of the aquifer, and when there are errors in the pressure, production or geologic data. INTRODUCTION The efficient operation of an oil or gas reservoir requires that the important characteristics of the reservoir be determined soon after its discovery. It is especially desirable to evaluate the pressure-production relationship quickly, for this relationship provides a basis for deducing the type of production mechanism that is operative, and for making pressure predictions. The pressure predictions, in turn, provide a basis for calculating efficient rates of production, determining whether water or gas should be injected, etc. The importance of pressure prediction is such that forecasts should be made as accurate as possible, and the limits of error well defined. Historically, pressure forecasts for some fields have proved very accurate, while for others the forecasts were so erroneous that they resulted in the adoption of wrong, or at best, unnecessary production practices. Pressure predictions made for water-drive fields are especially subject to error. Accurate forecasting for these fields requires that much be known not only about the reservoir proper but about the adjacent water-filled rock as well. The water-containing rock, or aquifer, may extend for many miles, and often there is only meager data regarding its thickness, permeability and porosity. Much of the information must be inferred from the previous pressure behavior of the reservoir. A brief pressure history may provide little information about the characteristics of the aquifer. Hence, pressure predictions made early in the life of water-drive fields can be incorrect. The work described in this paper was done to determine the degree of reliability which can be expected of pressure predictions made within a few years after water-drive fields are discovered. Five fields, for which the original pressure predictions had been based on less than seven years' history, were re-examined with the aid of four to five years of additional pressure data. Where the predictions were inaccurate, the reasons for failure were ascertained. The studies were accomplished by use of the electric reservoir analyzer.' The analyzer was first adjusted to repeat the original pressure-production match using the same values for the various parameters as were used in the original study. Then, the actual production rates experienced during the time elapsed since the initial study were set into the analyzer, and the pressure behavior indicated by the machine for this period was compared with that which actually OCcurred. Where the pressure profile traced out by the analyzer deviated from the observed field behavior, the analyzer was readjusted to obtain a better over-all match. The old and the new solutions were compared to determine the reasons for any differences. COMPARISON OF PREDICTED RESERVOIR PRESSURE BEHAVIOR WITH ACTUAL PERFORMANCE Field A The original pressure-production match is entirely adequate as evidenced by the pressure match of the field's history subsequent to Jan., 1952 (see Fig. 1)'.

By X Ma

Kaolinite is of very fine particle size in nature and thus its dispersion plays a key role in the successful removal of kaolinite in iron ore flotation and selective flocculation processes. As the most widely used dispersant in the world, sodium silicate has been used as a standard dispersant for kaolinite in the iron ore industry. However, the actual effect of sodium silicate on the colloid stability of kaolinite particles and its dispersion mechanism remain unknown in the literature. In this work, the dispersion effect and dispersion mechanisms of some common inorganic and organic dispersants, including sodium silicate, polyphosphate and a low molecular weight polyacrylic acid, on kaolinite particles were systematically investigated through electrophoretic mobility and colloidal stability studies over a wide pH range. It was found that sodium silicate-kaolinite interactions only take place in the neutral and acidic pH range, while polyacrylic acid and polyphosphate interact with kaolinite from pH 3 to 10.5. Consequently, sodium silicate only disperses kaolinite at neutral and acidic pH. In contrast, polyacrylic acid and polyphosphate disperse kaolinite from pH 3 to 10.5, with strong dispersion effect observed at neutral and acidic pH. In the iron ore industry, selective fl occulation and reverse cationic fl otation, the most widely used flotation route, are both conducted at pH 10 to 10.5. The results of the present study show that, at such high pH, polyacrylic acid and polyphosphate are more effective dispersants of kaolinite, in comparison with sodium silicate.

Jul 11, 2011